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Fiber-like π-conjugated nanostructures are important components of flexible organic electronic and optoelectronic devices. To broaden the range of potential applications, one needs to control not only the length of these nanostructures, but the introduction of diverse functionality with spatially selective control. Here we report the synthesis of a crystalline-coil block copolymer of oligo(p-phenylenevinylene)-b-poly(2-vinylpyridine) (OPV5 -b-P2VP44 ), in which the basicity and coordinating/chelating ability of the P2VP segment provide a landscape for the incorporation of a variety of functional inorganic NPs. Through a self-seeding strategy, we were able to prepare monodisperse fiber-like micelles of OPV5 -b-P2VP44 with lengths ranging from 50 to 800 nm. Significantly, the exposed two ends of OPV core of these fiber-like micelles remained active toward further epitaxial deposition of OPV5 -b-PNIPAM49 and OPV5 -b-P2VP44 to generate uniform A-B-A and B-A-B-A-B segmented block comicelles with tunable lengths for each block. The P2VP domains in these (co-)micelles can be selectively decorated with inorganic and polymeric nanoparticles as well as metal oxide coatings, to afford hybrid fiber-like nanostructures. This work provides a versatile strategy toward the fabrication of narrow length dispersity continuous and segmented π-conjugated OPV-containing fiber-like micelles with the capacity to be decorated in a spatially selective way with varying functionalities.

Fast fashion, as a continuously growing part of the textile industry, is widely criticized for its excessive resource use and high generation of textiles. To reduce its environmental impacts, numerous efforts are focused on finding sustainable and eco-friendly approaches to textile recycling. However, waste textiles and fibers are still mainly disposed of in landfills or by incineration after their service life and thereby pollute the natural environment, as there is still no effective strategy to separate natural fibers from chemical fibers. Herein, a green chemistry strategy is developed for the separation and regeneration of waste textiles at the molecular level. Cellulose/wool keratin composite fibers and multicomponent fibers are regenerated from waste textiles via a green chemical process. The strategy attempts to reduce the large amount of waste textiles generated by the fast-developing fashion industry and provide a new source of fibers, which can also address the fossil fuel reserve shortages caused by chemical fiber industries and global food shortages caused by natural fiber production.

Graphene oxide has been used as an adsorbent in wastewater treatment. However, the hydrophily and dispersibility in aqueous solution limit its practical application in environmental protection. In this paper, a novel, environmentally friendly adsorbent, chitosan and chitosan-graphene oxide aerogels with a diverse shape, large specific surface area, and unique porous structure were prepared by a freeze-drying method. The structure of the adsorbents was investigated using scanning electron microscopy, Fourier transform-infrared spectroscopy, and X-ray diffraction (XRD); the specific surface area and swelling capability were also characterized. In addition, removal of diesel oil from seawater by chitosan aerogel (CSAG) and chitosan-graphene oxide aerogel (AGGO-1 and AGGO-2) was studied and batch adsorption experiments were carried out as a function of different adsorbent dosages (0-6 g), contact time (0-120 minutes), pH (3-9), and initial concentrations of oil residue (3-30 g/L) to determine the optimum condition for the adsorption of residue oil from seawater. The results showed that the chitosan-graphene oxide aerogels were more effective to remove diesel oil from seawater compared with pure chitosan aerogel. A removal efficiency ≥ 95% of the chitosan-graphene oxide aerogels could be achieved easily at the initial concentrations of 20 g/L, which indicated that the chitosan-graphene oxide aerogels can be used to treat the industrial oil leakage or effluent in the natural water.

Several continuous-time random walk (CTRW) models exist to predict the dynamics of DNA in micropost arrays, but none of them quantitatively describes the separation seen in experiments or simulations. In Part I of this series, we examine the assumptions underlying these models by observing single molecules of λ DNA during electrophoresis in a regular, hexagonal array of oxidized silicon posts. Our analysis takes advantage of a combination of single-molecule videomicroscopy and previous Brownian dynamics simulations. Using a custom-tracking program, we automatically identify DNA-post collisions and thus study a large ensemble of events. Our results show that the hold-up time and the distance between collisions for consecutive collisions are uncorrelated. The distance between collisions is a random variable, but it can be smaller than the minimum value predicted by existing models of DNA transport in post arrays. The current CTRW models correctly predict the exponential decay in the probability density of the collision hold-up times, but they fail to account for the influence of finite-sized posts on short hold-up times. The shortcomings of the existing models identified here motivate the development of a new CTRW approach, which is presented in Part II of this series.